• The Korean Journal of Applied Statistics
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• v.30 no.3
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• pp.453-462
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• 2017

Double propensity score adjustment is an analytic solution to address bias due to incomplete matching. However, it is difficult to estimate the standard error of the estimated treatment effect when using double propensity score adjustment. In this study, we propose two bootstrap methods to estimate the standard error. The first is a simple bootstrap method that involves drawing bootstrap samples from the matched sample using the propensity score as well as estimating the standard error from the bootstrapped samples. The second is a complex bootstrap method that draws bootstrap samples first from the original sample and then applies the propensity score matching to each bootstrapped sample. We examined the performances of the two methods using simulations under various scenarios. The estimates of standard error using the complex bootstrap were closer to the empirical standard error than those using the simple bootstrap. The simple bootstrap methods tended to underestimate. In addition, the coverage rates of a 95% confidence interval using the complex bootstrap were closer to the advertised rate of 0.95. We applied the two methods to a real data example and found also that the estimate of the standard error using the simple bootstrap was smaller than that using the complex bootstrap.

• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.719-730
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• 2017

The purpose of this study is to investigate how engineering design-based STEM research experience affects gifted students' creative engineering problem-solving propensity and attitude toward engineering. The students' creative engineering problem-solving propensity and attitude toward engineering were measured before and after the STEM research experience. The pre-/post-tests results were analyzed by paired t-test with the significance level of p <.05. The conclusions of the study are as follows: First, the engineering design based STEM research experience had a positive effect on the students' creative engineering problem-solving propensity. Over all, the average score of the creative engineering problem-solving propensity increased significantly (p <.05) after the STEM research experience. Second, the average score of gifted-students' attitude toward engineering had increased significantly after the integrated STEM research activities (p <.05). In addition, we analyzed the difference between pre-post results of both instruments based on the gifted students' desired career paths (natural science and engineering) and gender. The result shows that the students' career paths or gender did not affect the results in most of the sub-categories in both instruments. However, the STEM research experience had more positive effect on the female students than male students in term of their 'engineering design ability', which is one of the sub-categories of the creative engineering problem-solving propensity instrument.

• The International Journal of Costume Culture
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• v.7 no.2
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• pp.103-111
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• 2004

The shrinkproof-finished wool fibers treated with resin coating and chlorination methods were used to find out an optimal shrinkproof finishing method keeping the quality properties of wool fabric to manufacturers. Shrinkage during repeated washing, electrostatic propensity, thermal resistance and pilling propensity of shrinkproof-finished wool knits, and analysis of finishing methods were measured. Upon the results from the surface examination of shrinkproof-finished wool fibers, the patterns of scale layer and degree of scale removal were subject to change according to the finishing processes. The shrink resistance was significantly enhanced on repeated washing of shrinkproof-finished knits, especially, chlorinated wool. Addition of strong physical force and alkali detergent applied in this washing experiment brought about superior effects with the low shrinkage rate although it was very severe washing conditions for wool fabrics. The results from the washing experiment implies that shrinkproof-finished knitted fabrics can be machine washed at individual households with other ordinary laundry. There was some changes and variation found in thermal resistance, electrostatic propensity, and pilling, however, it seems to be minor within standard limits. Therefore, shrinkproof-finished knitted fabrics did not bring serious changes to other physical properties comparing with original wool, which helps consumers handle wool knitted clothes more conveniently.

• Journal of Fashion Business
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• v.16 no.5
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• pp.130-145
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• 2012

The purpose of this study is to investigate the influence of cause-related marketing on consumer attitude for fashion brand in terms of brand familiarity, consumer's propensity for data processing and types of advertising. The design of this study is comprised of 2(brand familiarity : high vs low)${\times}$ 2(consumer's propensity for data processing : high vs low), designed with three mixed elements. The subjects of this study are 308 male and females in twenties or thirties from the area of Seoul, Kyunggi, Busan and Daegu. Data analysis is carried out through T-test, and ANOVA. The results of this study are as follows. First, when fashion brand pursues cause-related marketing, brand familiarity, consumer's propensity for data processing and types of advertising have statistically interaction effect on consumer's preference. Second, rational appeals in advertising have no significant interaction effect on consumer's preference in terms of brand familiarity. Rational appeals are preferred to Emotional appeals in both familiar and unfamiliar brand. Third, when fashion brand pursue cause-related marketing, brand familiarity, consumer's propensity for data processing, and the types of advertising have no significant interaction effect on consumer's preference.

• Journal of the Korean Society of Costume
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• v.48
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• pp.37-52
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• 1999

The purpose of this study was to find out the clothing-consumption propensity(CCP) and to classify consumption types in CCP and to classify consumption types in CCP and to compare the classfied groups on their consumer characteristics among Korean female X-generation. The survey method was conducted for this study. The subjects are 477 Koran femal X-generation whose age ranges from 18 to 29 and who reside in Seoul and its adjoined areas. The span of the survey was February through March in 1998. the results were analyzed by using of SPSS/PC+package. 1. The clothing consumption motives among the female X-generation were the sensuous satisfaction for posession motive the were practical necessity of the purcahse successively in order. The clothing consumption attitude were the practical electicism the effective value the favorable attitude on low price goods toward sale items and the self-control over their consumption. 2. According to the CCP consumers were classified into five groups: electice and practical group ostentatious and extravagant group passive and economical group sensuous and practical group and sale-fond group. The respective group showed significant difference in the nine factors of the CCP. 3. Consumtion type group had significantly difference in lifestyle among consumer factor and materialistic propensity influence of economic recession follow consumption among social influence factors.

• Journal of Information Processing Systems
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• v.9 no.1
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• pp.157-172
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• 2013

There are many recommendation systems available to provide users with personalized services. Among them, the most frequently used in electronic commerce is 'collaborative filtering', which is a technique that provides a process of filtering customer information for the preparation of profiles and making recommendations of products that are expected to be preferred by other users, based on such information profiles. Collaborative filtering systems, however, have in their nature both technical issues such as sparsity, scalability, and transparency, as well as security issues in the collection of the information that becomes the basis for preparation of the profiles. In this paper, we suggest a movie recommendation system, based on the selection of optimal personal propensity variables and the utilization of a secure collaborating filtering system, in order to provide a solution to such sparsity and scalability issues. At the same time, we adopt 'push attack' principles to deal with the security vulnerability of collaborative filtering systems. Furthermore, we assess the system's applicability by using the open database MovieLens, and present a personal propensity framework for improvement in the performance of recommender systems. We successfully come up with a movie recommendation system through the selection of optimal personalization factors and the embodiment of a safe collaborative filtering system.

• Korean Journal of Human Ecology
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• v.22 no.1
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• pp.117-129
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• 2013

The purpose of this study is to examine the factors affecting on CRPI (capability of retirement planning and implementing) and to identify the critical point of financial factors to increase CRPI. 908 Korean individuals' data were used for descriptive statistics, t-test, F-test, and Generalized Linear Mixed Model Analysis. As a result, CRPI was influenced by attitude toward retirement planning, gender, income, and propensity to save. Some mid-group did not make a significant difference in CRPI compared to the lower-group. Men were more capable at CRPI than women in terms of sense of independence and getting a consulting service. Most consumers appear to have difficulty in calculating their retirement fund. People who have income over 3,000,000 won have dramatically greater CRPI than people who have income under 3,000,000 won. And people who have saving ratio over 23% have significantly greater CRPI than people who have propensity to save under 23%. The monthly income 3,000,000 won and propensity to save 23% were considered as critical points related to CRPI.

• Journal of Sasang Constitutional Medicine
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• v.28 no.1
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• pp.11-18
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• 2016

Objectives The body shape was a key information for diagnosing the Sasang constitution (SC) in Sasang constitutional medicine. The aim of this study was to compare the body shapes and mainly focusing on the Korean and Chinese-KoreanMethods We calculated the propensity score for each SC type in males and females separately, and compared body shape including 8 circumference and 5 width between Korean and Chinese-Korean according to the sex and SC.Results Koreans have larger trunk and hip area compared to Chinese-Koreans, while Chinese-Koreans have larger abdomen compared with Koreans. Most variables were significantly different among SC types, for both Korean and Chinese-Korean. Especially, the Taeumin (TE) type has the largest body shape compared with the other SC types, it was similar between Korean and Chinese-Korean.Conclusions This study showed that the TE type has the largest body shape, followed by Soyangin (SY) and Soeumin (SE) in order, for both Korean and Chinese-Korean respectively. These results suggests that the body shape of Chinese-Korean is similar with Korean based on SC type.

• The Research Journal of the Costume Culture
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• v.12 no.6 s.53
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• pp.945-952
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• 2004

Shrink-resist effects and properties of the knitted fabrics from wool/acrylic(W/A) fiber blends were determined to find out an optimal blending ratio keeping the quality properties of wool products. The test fabrics were knitted by a weft knitting machine with all needle knitting structure ($0{\times}0$ rib) under the same knitting conditions with five different types of yarns: $W100\%,\;A100\%$, and W/A blended yarns(70/30, 50/50, 30/70). Shrinkage during repeated washing, electrostatic propensity, thermal resistance and pilling propensity of W/A knits. The shrink resistance was significantly enhanced on repeated washing of W/A knits, especially, over $50\%$ acrylic blended knits. Addition of strong physical force and alkali detergent applied in this washing experiment brought about superior effects with the low shrinkage rate although it was very severe washing conditions for wool fabrics. The results from the washing experiment implies that W/A blend knits can be machine washed at individual households with other ordinary laundry. There was some changes and variation found in thermal resistance, electrostatic propensity, and pilling. W/A 50/50 blended knits did not bring serious changes to other physical properties comparing with original wool, which helps consumers care wool knitted clothes more conveniently.

• Journal of Families and Better Life
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• v.25 no.3 s.87
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• pp.137-149
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• 2007

This study explores diverse consumer characteristics pursuant to whether the consumers in question have purchased luxury goods, and it also explores the variables that tend to influence such purchases. Furthermore, the relationship between consumers' purchases of, propensity for and preference toward luxury goods is researched, and an analysis is also conducted on the degrees of influence that consumer purchases of luxury goods have on consumer propensity and preference for luxury goods. The results show that the experience of such purchases determines the diverse characteristics of consumers in such areas as age, expenditures and overseas travel. In addition, the propensity of consumers to buy luxury goods is related to the tendency toward trends, self-planning, rationality and economic efficiency, while the preference of consumers is linked to the tendency toward trends, self-realization and rationality. This study aims to analyze and understand the consumer group of college women in their 20s, and it also seeks to help establish policies that will provide consumer education so badly needed by such women who are or who will be the main players of their respective household economies and rates of consumption.